Regulating dynamotor



Nov. 6, 1928. 1,690,142

H. L. TANNER RE GULA'I' I NG DYNAMOTOR Filed July 26, 1927 IN VEN TOR BY Har ryLT Zner 9 26 ATTORNEYS Patented Nov. 6, 192 8.

UNITED. STATES, PATENT OFFICE.

HARRY L. TANNER, OI BROOKLYN, 'NEW YORK, ASSIGNOB T0 FORD INS'IBUIEHT COMPANY, INC., OF LONG ISLAND CITY, NEW YORK. A COBIORATION OI NEW YORK.

nnounumo Dmmoron.

Application filed July 28,

This invention relates to electrical circuits in which it is desired to maintain a substantially constant potential across the line, but wherein disturbing influences tend to change the value of the potential in a preponderant direction. Thus, it is proposed to so control such a circuit that if it has an'occasional or an inherent tendency to sufl'er an undesired drop in potential, there will be a regulation that will ofi'set such tendency and substantially avoid a change in electrical pressure.

Such a circuit as has been referred to may, for example, be subject to a drop in potential, if no means he provided to counteract the drop, and, as applied to such a circuit, the present invention has the effect of boosting the voltage of the generator supplying the circuit. Obviously, if a circuit has a tendencyto acquire too high a voltage, this invention may be conformed to the requirements of such a condition, whereby the potential of the generator is bucked to an extent that will substantially maintain the potential constant.

In carrying out the invention, it is an object to effect the operation of a motor and a generator combined into one machine using a common field structure and to provide a regulating circuit associated with both the motor and the generator windings. The regulating circuit'includes means for so affecting the operation of the motor that the magnetic field is rotated as related to the motor brushes, while with res ct to the generator brushes it is rotated in a reverse sense. Accordingly, the change in electromotive-force of the generator offsets the tendency of a change in potential in the circuit to which it supplies current. Further means are provided, which are brought into action upon any overcorrective effort when the correction has attained its proper proportions.

Referring now to the drawings. Fig. 1 is a diagrammatic perspective View,

showing a load-carrying circuit and the reg ulating apparatus combined therewith;

Fig. 2 shows the motor end'of the dynamo electric machine included in the apparatus, and discloses the arrangement of the main and regulating poles and brushes;

Fig. 3 is a simplified diagram of the main circuits of the arrangement shown in Fig. 1 and 1927. serial inc. 208,487.

Fig. 4 is a similar view of a modified arrangement.

In the drawings, 1 and 2 represent direct current supply conductors across which field coils 3 and 3 are connected. These coils may be of any suitable number and encircle main pole-pieces, such as are shown at 4 and a in Fig. 2, two such coils and polepieces being shown for convenience. The pole-pieces 4,4 with the main field coils 3, 3 in place thereon are mounted in the usual field yoke, and are positioned so that an armature 5 may rotate between them, the armature being suitably mounted in any of the usual and well-known ways.

As shown in dot and dash lines in Fig. 1, a single armature 5 is common to both the motor M and the generator G, it being un derstood that the armature core has the armature windings of both the motor and the generator wound upon it. The armature winding of the motor is connected to the segments of a commutator 6, while the armature winding of -the generator is connected to the segments of another commutator 7 at the opposite endof the armature. If desired, the relationship may be preserved and other arrangements may be had, as, for instance, both commutators may be on one end of the armature, and, if desired, concentrically arranged. Another arrangement may be had wherein the motor commutator may be adjacent to the generator commutator.

Bearing on the motor commutator 6 are the main brushes 8 and .8, current being conveyed from the positive supply conductor 1 by a conductor 9 to the brush 8 that has segmental contact with commutator 6, passing through the motor armature winding and by a portion of the commutator 6to a brush 8. From the latter brush current travels by .way of conductor 10 to the generator main 11, which comes from the brush 12 that bears on the generator commutator 7. After passing through any suitable translating devices, as at X in Fig. 3, the current returns by the generatormain 13, the generator circuit continuing through the brush 14, generator commutator 7 and the generator winding, while the motor circuitgoes from the main 1.3 to the negative supply conductor 2.

Midway between the main fieldpole-pieces 4 and 4' are -mounted auxiliary pole-pieces 15 and 15, shown in Fig. 2, on which auxiliary field coils 16 and 16' are respectively wound. The coils 16 and 16' are in a regulating circuit which extends from the motor armature winding by the regulating brush 17 that bears on the motor commutator 6. A conductor 18 leads from brush 17 to coil 16, thence the regulating circuit continues by conductor 19 to the other coil 16', proceeding therefrom by a conductor 20 to a resistance 21. Whether the current flows through the resistance 21, or goes by a conductor 22 to a switch arm 23 depends upon whether a predetermined potential exists across the mains 11 and 13.

Current will flow from main 11 by conductor 24, through the coil of an electromagnet 25 and by conductor 26 to the main 13, and the switch arm 23 will rapidly vibrate in response to minor fluctuations in the potential across the mains 11, 13. The magnet 25 will attract the switch arm 23 in opposition to a spring 27 to its circuit-opening position whenever the potential starts to increase. Under these clrcumstances, the current will flow through the resistance 21, and return by a conductor 28 to the other regulating brush 29 and through the commutator 6 and the motor armature winding. The

v such shifting of the magnetic field is clock presence ofthe resistance 21 in circuit with the field coils 16 and 16 substantiall nullifies the effect of these coils upon t e field and no regulating action takes place.

When, however there is a sufficient va'ri ance in the otential across the mains 11 and 13, as, say, or exam he, a dro in potential the consequent wea ening o the coil 0 magnet 25, in that case, permits the spring 27 to become predominant, whereupon the switch arm 23 is moved into engagement with a contact 30. This results in the resistance 21 becoming short-circuited, so that the current which was described as flowing through the resistance goes instead by conductor 22 to the now closed switch arm 23,

passing to the contact 30, and proceeding by conductors 31 and 32 to conductor 28, and through regulating brush 29 and the motor armature winding, as before.

The effect of the removal of the resistance 21 from the regulating circuit is to cause the magnetization of the auxiliary polepieces 15 and 15' by their respective coils 16 and 16', thusproducing a shifting of the magnetic field. When the armature 5 and commutators 6 and 7 rotate counter-clockwise in unison, as indicated in Figs. 1 and 2,

wlse. v

Prior to the shifting of the magnetic field, i. e., before the auxiliary field coils 16 and 16 are effective, the neutral line is erpendicular to the direction of the lines of orce between the main north pole 4 and the main south pole 4", as in ordinary dynamoelectric machines. With the neutral line line 0-0, and the right hand main brush 8' is similarly above it, as shown in Fig. 2.

'At the generator end, the left hand main brush 12, shown in dotted lines in Fig. 2, is correspondingly set above the neutral line 0-0, while the main right hand generator brush 14.- is set below neutral line 0-0 in like manner. In other words, the neutral axis of the commutator lies between the brushes of the motor and the brushes of the generator, or the brushes for the motor are arranged on opposite sides of the neutral axis from those ofthe generator.

Consequentl when the resistance 21 is short circuited; there is the resultant mag netization of the auxiliary pole-pieces 15 and 15' by the auxiliarv coils 16 and 16, as explained. Under these circumstances, both the illustrated main north pole-piece 4 and the auxiliary north pole-piece 15' are magnetized, and there is a consequent north pole of the magnetic field which is displaced clockwise to some extent from the center 01 the main north pole-piece 4. Similarly, the now similtaneously magnetized main south pole-piece 4' and the auxiliary south polepiece 15 produce a consequent south pole of the magnetic field, which is correspondingly displaced clockwise from the center of the main south pole-piece 4. It is thus obvious that the magnetic field has been shifted.-

It is well known that the maximum electro-mdtive-force is obtained when the brushes are on the neutral magnetic line, and

is weakened when the brushes are moved away therefrom. Therefore, when the hereinbefore described shifting of the magnetic field takes place, the neutral magnetic line OO, shown in Fig. 2, will have been rotated clockwise away from the main motor brushes Band 8' and toward the generator brushes 12 a and 14 to a position O'O'. Manifestly, this'results in weaking the field with respect to the motor, since it is equivalent to moving the main motor brushes 8 and 8 away from the magnetic neutral line. On the other hand, it also amounts, in effect, to moving the generator brushes 12 and 14 toward the magneticneutral line, whereby the field is strengthened with respect to thegenerator.

Inasmuch as the voltage across the direct current supply conductors 1 and 2 remains substantially the same, and must be responded to by the motor portion of the dynamo-electric machine, the speed of the armature 5 is increased by way of compensation. Hence, the generator is operated at a higher rate, and, with its brushes 12 and 14 arranged reversely' to the magnetic neutral line as. compared with the motor brushes 8 and 8, so that the poles as related to the generator are strengthened, there is a re? sulting further increased electro-motiveforce by the generator. When the electromotive-force reaches its predetermined value" Upon the opening of the switch by the attraction of its switch arm .23, the resist-- ance 21 is again included in the regulating circuit. As previously explained this substantially nullifies the effect of the regulating coils 16 and 16, and it is apparent that the correction for the change in potential is terminated without an over-correction. In practice, the correction for a change of o'- tential is begunand terminated so quic ly that the armature 23 vibrates rapidly and the potential is maintained substantially constant. c

As set forth hereinbefore and easily understood from the s im lified diagram of Fig. 3, the current flowing from the direct current suppiv conductor 1 flows throu h brush 8 and the armature of the motor 1, continuing by brush 8' and conductor 10 to the generator main 11, through the translating device or devices X, and back by generator main 13 to the negative supply conductor 2. In the application of the invention illustrated in Figs. 1 and 3, the translating device or devices X are supplied with current developed by the generator G, which flows from the generator brush 12 through the conductor 11, in the same direction as the-flow of current from the motor M, thecurrent from both the generator G and motor M passing through the translating device or devices X, the current from geneiator G returning thereto by conductor 13 and brush 14, while the motor current re turns by way of the negative supply conductor 2. In accordance with What has been previously set forth herein, when the demands on the generator mains 11, 13 tend to cause adrop. in potential across these mains, the apparatus described in connection with Fig. 1 acts to speed up the operation of the generator G thereby increasing its electromotive-iorce. A

While, in'the illustrat d embodiment of the invention two auxiliary brushes 17 and 29 have been employed, the invention may be practiced with excellent results with the use of only one auxiliary brush. In such case, the brush 29, for example, may be dis pensed with, and the brush 17 retained. Under these circumstances; the conductor 28 will be connected to the main brush 8', in-

stead of to auxiliary brush 29 which is then discarded, the circuits being otherwise unchanged. It is also possible to operate the electrical apparatus herein disclosed by dispensing with both auxiliary brushes 17 and 29, in which case the conductors 18 and 28 are in some instances, but in which it will be understood that a mechanical unity equivalent to that of the apparatus of Fig. 1 is preserved in the sense that the generator is responsive to the motor drive to roduce the same efi'ects as were described 1n the first set forth form of the invention.

I claim:

1. In combination, an electrical circuit, a generator connected thereacross and having commutator brushes, a motor in unitary combination with the generator, and regulating means controlled by the potential of said circuit to shift the magnetic field with respect to said brushes thereby altering the action of the motor in response to potential variations of said circuit thereby changing the operation of the generator.

2. In combination, a dynamo electric ma chine formed in part as a motor having commutator brushes and inpart as a generator, at current supply circuit for the motor part, a circuit energized by the generator part and subject to potential variation, and a neutralize said electro-magnetic meanso and controlling means responsive to potential variation in the generator circuit to nullify said neutralizing means to efi'ect a shifting of the magnetic field with respect to said brushes to vary its strength in reverse senses wit respect to the motor and generator and cause the latter to tend to ofiset the potential variance.

, 4. In combination, a dynamo electric machine constituting a unitary motor and generator having commutator brushes, main and auxiliary field magnets and armatures arto the motor and enerator brushes to cause the generator to 0 set the potential variance.

5. In combination, a dynamo electric machine constructed to form a motor having main and auxiliary commutator brushes an also to form a generator concomitantly operable with the motor and having commutator brushes, 0. motor supply circuit, a circuit energized by the generator subject to potential variance, main and. auxiliary-field magnets, and a regulating circuit connected to some of the motor brushes including an auxiliary brush and comprising resistance adapted to neutralize the efiect of said auxiliary field magnets, and controlling means responsive to potential variance in the generator circuit to short circuit said resistance and efi'ect'a shifting of themagnetlc field in relatively opposite senses with respect to the motor and generator brushes to offset,

the potential variance.

6. In combination, a dynamo electric machine constitutin a unitary motor and generator having mam and auxiliary field ma nets and unified armatures provided wit commutators, motor and generator commu-. tator brushes the neutral line of the magnetic field lying between those of the former and latter, a circuit energized by the generator, and are ulating circuit comprising resistance in'circuit with the auxiliary field magnets adapted to, neutralize the effect thereof, and control means responsive to potential variation in the generator circuit to short circuit said resistance and cause a shiftin of the magnetic field relative to said brus es to vary the field strength in reverse senses with respect to the-motor and generator.

7 In combination, a dynamo-electric inachine constituting a unitary motor and generator havin a magnetic field and commutating means including brushes and arranged so that the neutral axis of the commutating means lies between the brushes of the motor and the brushes of'the generator and meansto relatively shift the magnetic field and the brushes in 1 response to a variationv of potential. 4

8. In a dynamotor, a motor and a generator having a common magnetic field and commutating means havin a neutral-axis and including brushes for e motor and for the generator arranged on opposite sides of the neutral axis and means to alter the relation between the neutral axis and the brushes in response to variations of potential.

9. In combination, a dynamo-electric machine constituting a unita motor and generator included in electrical circuits and having a magnetic field, the motor and generator each bein provided with commutating means inclu'ing brushes and arran ed so that the neutral axis of the commutating means lies between the brushes of the motor and the brushes of the generator and means responsive to variations of potential for relatively shifting the magnetic field and the brushes.

10. In a dynamotor, a motor and a generator having a common magnetic field and each rovided with commutating means including brushes and arranged so that theneutral axis oi the commutatin means of the motor lies on one side of the rushes for the motor and the neutral axis of the commutating means of the enerator lies on the op osite side of the brus es for the generator an means to alter .the relation between the neutral axis and the brushes in response to variations of potential.

11. In combination, a dynamo-electric machine constituting a unitar motor and enerator havin main an auxiliary eld magnets, uni edarmatures provided with commutating means including brushes and arran ed so that the neutral axis of the commutating means lies between the brushes of the motor and the brushes of the generator, a motor supply circuit, a circuit energized by the generator,..a regulating circuit comprising a resistance for neutralizing the auxiliary field magnets when a certain potentialprevails in the generator circuit and means including an electro magnetic switch responsive to variations of potential in the generator circuit to short circuit the resistance to cause a relative, shifting of the magnetic field and the brushes to vary the strength of the magnetic field in reverse senses with respect to the" motor and generator to cause the latter to tend to offset the variations of potential in the generator circuit.

chine constituting a unitay motor and enerator havin main an auxiliary eld magnets, uni ed armatures provided with commutating means including brushes and arranged so that the neutral axis of the comlea 12. In combination, a dynamo-electric mamutating means lies between the brushes of the motor and the brushes of the generator, a motor supply circuit, a circuit energized by the generator, a re prising a resistance or neutralizing the auxiliary field magnets when a certainpolating. circuit, com- {tantial prevails in the generator circuit,

means including an electro magnetic switch ator to cause the latter to tend to ofisct the responsive to variations of potential in the variations of potential in the generator cirgenerator circuit to short circuit the resists cuit and anti-sparking means associated with 10 I ance to cause a relative shifting of the said switch.

5 magnetic field and the brushes to vary the In testimony whereof Iafiix my signature.

strength of the magnetic field in reverse senses with respect to the motor and generi HARRY L. TANNER. I 

